The 9/11 Memorial Stair Climbs 9/11 Memorial Stair Climbs honor FDNY firefighters who made the ultimate sacrifice. Each 9/11 Memorial Stair Climb participants pays tribute to a FDNY firefighter by climbing or walking the equivalent of the 110 stories of the World Trade Center.

On September 11, 2001, FDNY firefighters faced an unprecedented physical challenge, with many climbing as high as the 70th to 80th floors of the North Tower (Tower 1). Because the elevators were non-functional in the impact zones, firefighters had to carry approximately 60 to 100 pounds of gear—including hoses, axes, and oxygen tanks—up the narrow stairwells. Most units reached between the 40th and 60th floors before the South Tower collapsed, which triggered the evacuation order for the North Tower. One of the highest documented points reached was by Captain Patrick Brown and his men of Ladder 3, who were reported to be on the 40th floor and still ascending when they were lost. In the South Tower (Tower 2), which was struck second but collapsed first, units were generally lower in the building at the time of collapse, though some had reached the 70th floor sky lobby. Today, the "9/11 Memorial Stair Climb" events held across the U.S. honor these heroes by having participants climb the equivalent of 110 flights of stairs, representing the total height of the World Trade Center towers.